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<div class="title">IVFUtilsSelect2.cu</div>  </div>
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<div class="contents">
<div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno">    1</span>&#160;<span class="comment"></span></div>
<div class="line"><a name="l00002"></a><span class="lineno">    2</span>&#160;<span class="comment">/**</span></div>
<div class="line"><a name="l00003"></a><span class="lineno">    3</span>&#160;<span class="comment"> * Copyright (c) 2015-present, Facebook, Inc.</span></div>
<div class="line"><a name="l00004"></a><span class="lineno">    4</span>&#160;<span class="comment"> * All rights reserved.</span></div>
<div class="line"><a name="l00005"></a><span class="lineno">    5</span>&#160;<span class="comment"> *</span></div>
<div class="line"><a name="l00006"></a><span class="lineno">    6</span>&#160;<span class="comment"> * This source code is licensed under the CC-by-NC license found in the</span></div>
<div class="line"><a name="l00007"></a><span class="lineno">    7</span>&#160;<span class="comment"> * LICENSE file in the root directory of this source tree.</span></div>
<div class="line"><a name="l00008"></a><span class="lineno">    8</span>&#160;<span class="comment"> */</span></div>
<div class="line"><a name="l00009"></a><span class="lineno">    9</span>&#160;</div>
<div class="line"><a name="l00010"></a><span class="lineno">   10</span>&#160;<span class="comment">// Copyright 2004-present Facebook. All Rights Reserved.</span></div>
<div class="line"><a name="l00011"></a><span class="lineno">   11</span>&#160;</div>
<div class="line"><a name="l00012"></a><span class="lineno">   12</span>&#160;<span class="preprocessor">#include &quot;IVFUtils.cuh&quot;</span></div>
<div class="line"><a name="l00013"></a><span class="lineno">   13</span>&#160;<span class="preprocessor">#include &quot;../utils/DeviceUtils.h&quot;</span></div>
<div class="line"><a name="l00014"></a><span class="lineno">   14</span>&#160;<span class="preprocessor">#include &quot;../utils/Select.cuh&quot;</span></div>
<div class="line"><a name="l00015"></a><span class="lineno">   15</span>&#160;<span class="preprocessor">#include &quot;../utils/StaticUtils.h&quot;</span></div>
<div class="line"><a name="l00016"></a><span class="lineno">   16</span>&#160;<span class="preprocessor">#include &quot;../utils/Tensor.cuh&quot;</span></div>
<div class="line"><a name="l00017"></a><span class="lineno">   17</span>&#160;<span class="preprocessor">#include &lt;limits&gt;</span></div>
<div class="line"><a name="l00018"></a><span class="lineno">   18</span>&#160;</div>
<div class="line"><a name="l00019"></a><span class="lineno">   19</span>&#160;<span class="comment">//</span></div>
<div class="line"><a name="l00020"></a><span class="lineno">   20</span>&#160;<span class="comment">// This kernel is split into a separate compilation unit to cut down</span></div>
<div class="line"><a name="l00021"></a><span class="lineno">   21</span>&#160;<span class="comment">// on compile time</span></div>
<div class="line"><a name="l00022"></a><span class="lineno">   22</span>&#160;<span class="comment">//</span></div>
<div class="line"><a name="l00023"></a><span class="lineno">   23</span>&#160;</div>
<div class="line"><a name="l00024"></a><span class="lineno">   24</span>&#160;<span class="keyword">namespace </span>faiss { <span class="keyword">namespace </span>gpu {</div>
<div class="line"><a name="l00025"></a><span class="lineno">   25</span>&#160;</div>
<div class="line"><a name="l00026"></a><span class="lineno">   26</span>&#160;constexpr <span class="keyword">auto</span> kMax = std::numeric_limits&lt;float&gt;::max();</div>
<div class="line"><a name="l00027"></a><span class="lineno">   27</span>&#160;constexpr <span class="keyword">auto</span> kMin = std::numeric_limits&lt;float&gt;::min();</div>
<div class="line"><a name="l00028"></a><span class="lineno">   28</span>&#160;</div>
<div class="line"><a name="l00029"></a><span class="lineno">   29</span>&#160;<span class="comment">// This is warp divergence central, but this is really a final step</span></div>
<div class="line"><a name="l00030"></a><span class="lineno">   30</span>&#160;<span class="comment">// and happening a small number of times</span></div>
<div class="line"><a name="l00031"></a><span class="lineno">   31</span>&#160;<span class="keyword">inline</span> __device__ <span class="keywordtype">int</span> binarySearchForBucket(<span class="keywordtype">int</span>* prefixSumOffsets,</div>
<div class="line"><a name="l00032"></a><span class="lineno">   32</span>&#160;                                            <span class="keywordtype">int</span> size,</div>
<div class="line"><a name="l00033"></a><span class="lineno">   33</span>&#160;                                            <span class="keywordtype">int</span> val) {</div>
<div class="line"><a name="l00034"></a><span class="lineno">   34</span>&#160;  <span class="keywordtype">int</span> start = 0;</div>
<div class="line"><a name="l00035"></a><span class="lineno">   35</span>&#160;  <span class="keywordtype">int</span> end = size;</div>
<div class="line"><a name="l00036"></a><span class="lineno">   36</span>&#160;</div>
<div class="line"><a name="l00037"></a><span class="lineno">   37</span>&#160;  <span class="keywordflow">while</span> (end - start &gt; 0) {</div>
<div class="line"><a name="l00038"></a><span class="lineno">   38</span>&#160;    <span class="keywordtype">int</span> mid = start + (end - start) / 2;</div>
<div class="line"><a name="l00039"></a><span class="lineno">   39</span>&#160;</div>
<div class="line"><a name="l00040"></a><span class="lineno">   40</span>&#160;    <span class="keywordtype">int</span> midVal = prefixSumOffsets[mid];</div>
<div class="line"><a name="l00041"></a><span class="lineno">   41</span>&#160;</div>
<div class="line"><a name="l00042"></a><span class="lineno">   42</span>&#160;    <span class="comment">// Find the first bucket that we are &lt;=</span></div>
<div class="line"><a name="l00043"></a><span class="lineno">   43</span>&#160;    <span class="keywordflow">if</span> (midVal &lt;= val) {</div>
<div class="line"><a name="l00044"></a><span class="lineno">   44</span>&#160;      start = mid + 1;</div>
<div class="line"><a name="l00045"></a><span class="lineno">   45</span>&#160;    } <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00046"></a><span class="lineno">   46</span>&#160;      end = mid;</div>
<div class="line"><a name="l00047"></a><span class="lineno">   47</span>&#160;    }</div>
<div class="line"><a name="l00048"></a><span class="lineno">   48</span>&#160;  }</div>
<div class="line"><a name="l00049"></a><span class="lineno">   49</span>&#160;</div>
<div class="line"><a name="l00050"></a><span class="lineno">   50</span>&#160;  <span class="comment">// We must find the bucket that it is in</span></div>
<div class="line"><a name="l00051"></a><span class="lineno">   51</span>&#160;  assert(start != size);</div>
<div class="line"><a name="l00052"></a><span class="lineno">   52</span>&#160;</div>
<div class="line"><a name="l00053"></a><span class="lineno">   53</span>&#160;  <span class="keywordflow">return</span> start;</div>
<div class="line"><a name="l00054"></a><span class="lineno">   54</span>&#160;}</div>
<div class="line"><a name="l00055"></a><span class="lineno">   55</span>&#160;</div>
<div class="line"><a name="l00056"></a><span class="lineno">   56</span>&#160;<span class="keyword">template</span> &lt;<span class="keywordtype">int</span> ThreadsPerBlock,</div>
<div class="line"><a name="l00057"></a><span class="lineno">   57</span>&#160;          <span class="keywordtype">int</span> NumWarpQ,</div>
<div class="line"><a name="l00058"></a><span class="lineno">   58</span>&#160;          <span class="keywordtype">int</span> NumThreadQ,</div>
<div class="line"><a name="l00059"></a><span class="lineno">   59</span>&#160;          <span class="keywordtype">bool</span> Dir&gt;</div>
<div class="line"><a name="l00060"></a><span class="lineno">   60</span>&#160;__global__ <span class="keywordtype">void</span></div>
<div class="line"><a name="l00061"></a><span class="lineno">   61</span>&#160;pass2SelectLists(Tensor&lt;float, 2, true&gt; heapDistances,</div>
<div class="line"><a name="l00062"></a><span class="lineno">   62</span>&#160;                 Tensor&lt;int, 2, true&gt; heapIndices,</div>
<div class="line"><a name="l00063"></a><span class="lineno">   63</span>&#160;                 <span class="keywordtype">void</span>** listIndices,</div>
<div class="line"><a name="l00064"></a><span class="lineno">   64</span>&#160;                 Tensor&lt;int, 2, true&gt; prefixSumOffsets,</div>
<div class="line"><a name="l00065"></a><span class="lineno">   65</span>&#160;                 Tensor&lt;int, 2, true&gt; topQueryToCentroid,</div>
<div class="line"><a name="l00066"></a><span class="lineno">   66</span>&#160;                 <span class="keywordtype">int</span> k,</div>
<div class="line"><a name="l00067"></a><span class="lineno">   67</span>&#160;                 IndicesOptions opt,</div>
<div class="line"><a name="l00068"></a><span class="lineno">   68</span>&#160;                 Tensor&lt;float, 2, true&gt; outDistances,</div>
<div class="line"><a name="l00069"></a><span class="lineno">   69</span>&#160;                 Tensor&lt;long, 2, true&gt; outIndices) {</div>
<div class="line"><a name="l00070"></a><span class="lineno">   70</span>&#160;  constexpr <span class="keywordtype">int</span> kNumWarps = ThreadsPerBlock / kWarpSize;</div>
<div class="line"><a name="l00071"></a><span class="lineno">   71</span>&#160;</div>
<div class="line"><a name="l00072"></a><span class="lineno">   72</span>&#160;  __shared__ <span class="keywordtype">float</span> smemK[kNumWarps * NumWarpQ];</div>
<div class="line"><a name="l00073"></a><span class="lineno">   73</span>&#160;  __shared__ <span class="keywordtype">int</span> smemV[kNumWarps * NumWarpQ];</div>
<div class="line"><a name="l00074"></a><span class="lineno">   74</span>&#160;</div>
<div class="line"><a name="l00075"></a><span class="lineno">   75</span>&#160;  constexpr <span class="keyword">auto</span> kInit = Dir ? kMin : kMax;</div>
<div class="line"><a name="l00076"></a><span class="lineno">   76</span>&#160;  BlockSelect&lt;float, int, Dir, Comparator&lt;float&gt;,</div>
<div class="line"><a name="l00077"></a><span class="lineno">   77</span>&#160;            NumWarpQ, NumThreadQ, ThreadsPerBlock&gt;</div>
<div class="line"><a name="l00078"></a><span class="lineno">   78</span>&#160;    heap(kInit, -1, smemK, smemV, k);</div>
<div class="line"><a name="l00079"></a><span class="lineno">   79</span>&#160;</div>
<div class="line"><a name="l00080"></a><span class="lineno">   80</span>&#160;  <span class="keyword">auto</span> queryId = blockIdx.x;</div>
<div class="line"><a name="l00081"></a><span class="lineno">   81</span>&#160;  <span class="keywordtype">int</span> num = heapDistances.getSize(1);</div>
<div class="line"><a name="l00082"></a><span class="lineno">   82</span>&#160;  <span class="keywordtype">int</span> limit = utils::roundDown(num, kWarpSize);</div>
<div class="line"><a name="l00083"></a><span class="lineno">   83</span>&#160;</div>
<div class="line"><a name="l00084"></a><span class="lineno">   84</span>&#160;  <span class="keywordtype">int</span> i = threadIdx.x;</div>
<div class="line"><a name="l00085"></a><span class="lineno">   85</span>&#160;  <span class="keyword">auto</span> heapDistanceStart = heapDistances[queryId];</div>
<div class="line"><a name="l00086"></a><span class="lineno">   86</span>&#160;</div>
<div class="line"><a name="l00087"></a><span class="lineno">   87</span>&#160;  <span class="comment">// BlockSelect add cannot be used in a warp divergent circumstance; we</span></div>
<div class="line"><a name="l00088"></a><span class="lineno">   88</span>&#160;  <span class="comment">// handle the remainder warp below</span></div>
<div class="line"><a name="l00089"></a><span class="lineno">   89</span>&#160;  <span class="keywordflow">for</span> (; i &lt; limit; i += blockDim.x) {</div>
<div class="line"><a name="l00090"></a><span class="lineno">   90</span>&#160;    heap.add(heapDistanceStart[i], i);</div>
<div class="line"><a name="l00091"></a><span class="lineno">   91</span>&#160;  }</div>
<div class="line"><a name="l00092"></a><span class="lineno">   92</span>&#160;</div>
<div class="line"><a name="l00093"></a><span class="lineno">   93</span>&#160;  <span class="comment">// Handle warp divergence separately</span></div>
<div class="line"><a name="l00094"></a><span class="lineno">   94</span>&#160;  <span class="keywordflow">if</span> (i &lt; num) {</div>
<div class="line"><a name="l00095"></a><span class="lineno">   95</span>&#160;    heap.addThreadQ(heapDistanceStart[i], i);</div>
<div class="line"><a name="l00096"></a><span class="lineno">   96</span>&#160;  }</div>
<div class="line"><a name="l00097"></a><span class="lineno">   97</span>&#160;</div>
<div class="line"><a name="l00098"></a><span class="lineno">   98</span>&#160;  <span class="comment">// Merge all final results</span></div>
<div class="line"><a name="l00099"></a><span class="lineno">   99</span>&#160;  heap.reduce();</div>
<div class="line"><a name="l00100"></a><span class="lineno">  100</span>&#160;</div>
<div class="line"><a name="l00101"></a><span class="lineno">  101</span>&#160;  <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = threadIdx.x; i &lt; k; i += blockDim.x) {</div>
<div class="line"><a name="l00102"></a><span class="lineno">  102</span>&#160;    outDistances[queryId][i] = smemK[i];</div>
<div class="line"><a name="l00103"></a><span class="lineno">  103</span>&#160;</div>
<div class="line"><a name="l00104"></a><span class="lineno">  104</span>&#160;    <span class="comment">// `v` is the index in `heapIndices`</span></div>
<div class="line"><a name="l00105"></a><span class="lineno">  105</span>&#160;    <span class="comment">// We need to translate this into an original user index. The</span></div>
<div class="line"><a name="l00106"></a><span class="lineno">  106</span>&#160;    <span class="comment">// reason why we don&#39;t maintain intermediate results in terms of</span></div>
<div class="line"><a name="l00107"></a><span class="lineno">  107</span>&#160;    <span class="comment">// user indices is to substantially reduce temporary memory</span></div>
<div class="line"><a name="l00108"></a><span class="lineno">  108</span>&#160;    <span class="comment">// requirements and global memory write traffic for the list</span></div>
<div class="line"><a name="l00109"></a><span class="lineno">  109</span>&#160;    <span class="comment">// scanning.</span></div>
<div class="line"><a name="l00110"></a><span class="lineno">  110</span>&#160;    <span class="comment">// This code is highly divergent, but it&#39;s probably ok, since this</span></div>
<div class="line"><a name="l00111"></a><span class="lineno">  111</span>&#160;    <span class="comment">// is the very last step and it is happening a small number of</span></div>
<div class="line"><a name="l00112"></a><span class="lineno">  112</span>&#160;    <span class="comment">// times (#queries x k).</span></div>
<div class="line"><a name="l00113"></a><span class="lineno">  113</span>&#160;    <span class="keywordtype">int</span> v = smemV[i];</div>
<div class="line"><a name="l00114"></a><span class="lineno">  114</span>&#160;    <span class="keywordtype">long</span> index = -1;</div>
<div class="line"><a name="l00115"></a><span class="lineno">  115</span>&#160;</div>
<div class="line"><a name="l00116"></a><span class="lineno">  116</span>&#160;    <span class="keywordflow">if</span> (v != -1) {</div>
<div class="line"><a name="l00117"></a><span class="lineno">  117</span>&#160;      <span class="comment">// `offset` is the offset of the intermediate result, as</span></div>
<div class="line"><a name="l00118"></a><span class="lineno">  118</span>&#160;      <span class="comment">// calculated by the original scan.</span></div>
<div class="line"><a name="l00119"></a><span class="lineno">  119</span>&#160;      <span class="keywordtype">int</span> offset = heapIndices[queryId][v];</div>
<div class="line"><a name="l00120"></a><span class="lineno">  120</span>&#160;</div>
<div class="line"><a name="l00121"></a><span class="lineno">  121</span>&#160;      <span class="comment">// In order to determine the actual user index, we need to first</span></div>
<div class="line"><a name="l00122"></a><span class="lineno">  122</span>&#160;      <span class="comment">// determine what list it was in.</span></div>
<div class="line"><a name="l00123"></a><span class="lineno">  123</span>&#160;      <span class="comment">// We do this by binary search in the prefix sum list.</span></div>
<div class="line"><a name="l00124"></a><span class="lineno">  124</span>&#160;      <span class="keywordtype">int</span> probe = binarySearchForBucket(prefixSumOffsets[queryId].data(),</div>
<div class="line"><a name="l00125"></a><span class="lineno">  125</span>&#160;                                        prefixSumOffsets.getSize(1),</div>
<div class="line"><a name="l00126"></a><span class="lineno">  126</span>&#160;                                        offset);</div>
<div class="line"><a name="l00127"></a><span class="lineno">  127</span>&#160;</div>
<div class="line"><a name="l00128"></a><span class="lineno">  128</span>&#160;      <span class="comment">// This is then the probe for the query; we can find the actual</span></div>
<div class="line"><a name="l00129"></a><span class="lineno">  129</span>&#160;      <span class="comment">// list ID from this</span></div>
<div class="line"><a name="l00130"></a><span class="lineno">  130</span>&#160;      <span class="keywordtype">int</span> listId = topQueryToCentroid[queryId][probe];</div>
<div class="line"><a name="l00131"></a><span class="lineno">  131</span>&#160;</div>
<div class="line"><a name="l00132"></a><span class="lineno">  132</span>&#160;      <span class="comment">// Now, we need to know the offset within the list</span></div>
<div class="line"><a name="l00133"></a><span class="lineno">  133</span>&#160;      <span class="comment">// We ensure that before the array (at offset -1), there is a 0 value</span></div>
<div class="line"><a name="l00134"></a><span class="lineno">  134</span>&#160;      <span class="keywordtype">int</span> listStart = *(prefixSumOffsets[queryId][probe].data() - 1);</div>
<div class="line"><a name="l00135"></a><span class="lineno">  135</span>&#160;      <span class="keywordtype">int</span> listOffset = offset - listStart;</div>
<div class="line"><a name="l00136"></a><span class="lineno">  136</span>&#160;</div>
<div class="line"><a name="l00137"></a><span class="lineno">  137</span>&#160;      <span class="comment">// This gives us our final index</span></div>
<div class="line"><a name="l00138"></a><span class="lineno">  138</span>&#160;      <span class="keywordflow">if</span> (opt == INDICES_32_BIT) {</div>
<div class="line"><a name="l00139"></a><span class="lineno">  139</span>&#160;        index = (long) ((<span class="keywordtype">int</span>*) listIndices[listId])[listOffset];</div>
<div class="line"><a name="l00140"></a><span class="lineno">  140</span>&#160;      } <span class="keywordflow">else</span> <span class="keywordflow">if</span> (opt == INDICES_64_BIT) {</div>
<div class="line"><a name="l00141"></a><span class="lineno">  141</span>&#160;        index = ((<span class="keywordtype">long</span>*) listIndices[listId])[listOffset];</div>
<div class="line"><a name="l00142"></a><span class="lineno">  142</span>&#160;      } <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00143"></a><span class="lineno">  143</span>&#160;        index = ((long) listId &lt;&lt; 32 | (<span class="keywordtype">long</span>) listOffset);</div>
<div class="line"><a name="l00144"></a><span class="lineno">  144</span>&#160;      }</div>
<div class="line"><a name="l00145"></a><span class="lineno">  145</span>&#160;    }</div>
<div class="line"><a name="l00146"></a><span class="lineno">  146</span>&#160;</div>
<div class="line"><a name="l00147"></a><span class="lineno">  147</span>&#160;    outIndices[queryId][i] = index;</div>
<div class="line"><a name="l00148"></a><span class="lineno">  148</span>&#160;  }</div>
<div class="line"><a name="l00149"></a><span class="lineno">  149</span>&#160;}</div>
<div class="line"><a name="l00150"></a><span class="lineno">  150</span>&#160;</div>
<div class="line"><a name="l00151"></a><span class="lineno">  151</span>&#160;<span class="keywordtype">void</span></div>
<div class="line"><a name="l00152"></a><span class="lineno">  152</span>&#160;runPass2SelectLists(Tensor&lt;float, 2, true&gt;&amp; heapDistances,</div>
<div class="line"><a name="l00153"></a><span class="lineno">  153</span>&#160;                    Tensor&lt;int, 2, true&gt;&amp; heapIndices,</div>
<div class="line"><a name="l00154"></a><span class="lineno">  154</span>&#160;                    thrust::device_vector&lt;void*&gt;&amp; listIndices,</div>
<div class="line"><a name="l00155"></a><span class="lineno">  155</span>&#160;                    IndicesOptions indicesOptions,</div>
<div class="line"><a name="l00156"></a><span class="lineno">  156</span>&#160;                    Tensor&lt;int, 2, true&gt;&amp; prefixSumOffsets,</div>
<div class="line"><a name="l00157"></a><span class="lineno">  157</span>&#160;                    Tensor&lt;int, 2, true&gt;&amp; topQueryToCentroid,</div>
<div class="line"><a name="l00158"></a><span class="lineno">  158</span>&#160;                    <span class="keywordtype">int</span> k,</div>
<div class="line"><a name="l00159"></a><span class="lineno">  159</span>&#160;                    <span class="keywordtype">bool</span> chooseLargest,</div>
<div class="line"><a name="l00160"></a><span class="lineno">  160</span>&#160;                    Tensor&lt;float, 2, true&gt;&amp; outDistances,</div>
<div class="line"><a name="l00161"></a><span class="lineno">  161</span>&#160;                    Tensor&lt;long, 2, true&gt;&amp; outIndices,</div>
<div class="line"><a name="l00162"></a><span class="lineno">  162</span>&#160;                    cudaStream_t stream) {</div>
<div class="line"><a name="l00163"></a><span class="lineno">  163</span>&#160;  constexpr <span class="keyword">auto</span> kThreadsPerBlock = 128;</div>
<div class="line"><a name="l00164"></a><span class="lineno">  164</span>&#160;</div>
<div class="line"><a name="l00165"></a><span class="lineno">  165</span>&#160;  <span class="keyword">auto</span> grid = dim3(topQueryToCentroid.getSize(0));</div>
<div class="line"><a name="l00166"></a><span class="lineno">  166</span>&#160;  <span class="keyword">auto</span> block = dim3(kThreadsPerBlock);</div>
<div class="line"><a name="l00167"></a><span class="lineno">  167</span>&#160;</div>
<div class="line"><a name="l00168"></a><span class="lineno">  168</span>&#160;<span class="preprocessor">#define RUN_PASS(NUM_WARP_Q, NUM_THREAD_Q, DIR)                         \</span></div>
<div class="line"><a name="l00169"></a><span class="lineno">  169</span>&#160;<span class="preprocessor">  do {                                                                  \</span></div>
<div class="line"><a name="l00170"></a><span class="lineno">  170</span>&#160;<span class="preprocessor">    pass2SelectLists&lt;kThreadsPerBlock,                                  \</span></div>
<div class="line"><a name="l00171"></a><span class="lineno">  171</span>&#160;<span class="preprocessor">                     NUM_WARP_Q, NUM_THREAD_Q, DIR&gt;                     \</span></div>
<div class="line"><a name="l00172"></a><span class="lineno">  172</span>&#160;<span class="preprocessor">      &lt;&lt;&lt;grid, block, 0, stream&gt;&gt;&gt;(heapDistances,                       \</span></div>
<div class="line"><a name="l00173"></a><span class="lineno">  173</span>&#160;<span class="preprocessor">                                   heapIndices,                         \</span></div>
<div class="line"><a name="l00174"></a><span class="lineno">  174</span>&#160;<span class="preprocessor">                                   listIndices.data().get(),            \</span></div>
<div class="line"><a name="l00175"></a><span class="lineno">  175</span>&#160;<span class="preprocessor">                                   prefixSumOffsets,                    \</span></div>
<div class="line"><a name="l00176"></a><span class="lineno">  176</span>&#160;<span class="preprocessor">                                   topQueryToCentroid,                  \</span></div>
<div class="line"><a name="l00177"></a><span class="lineno">  177</span>&#160;<span class="preprocessor">                                   k,                                   \</span></div>
<div class="line"><a name="l00178"></a><span class="lineno">  178</span>&#160;<span class="preprocessor">                                   indicesOptions,                      \</span></div>
<div class="line"><a name="l00179"></a><span class="lineno">  179</span>&#160;<span class="preprocessor">                                   outDistances,                        \</span></div>
<div class="line"><a name="l00180"></a><span class="lineno">  180</span>&#160;<span class="preprocessor">                                   outIndices);                         \</span></div>
<div class="line"><a name="l00181"></a><span class="lineno">  181</span>&#160;<span class="preprocessor">    return; </span><span class="comment">/* success */</span><span class="preprocessor">                                               \</span></div>
<div class="line"><a name="l00182"></a><span class="lineno">  182</span>&#160;<span class="preprocessor">  } while (0)</span></div>
<div class="line"><a name="l00183"></a><span class="lineno">  183</span>&#160;<span class="preprocessor"></span></div>
<div class="line"><a name="l00184"></a><span class="lineno">  184</span>&#160;<span class="preprocessor">#define RUN_PASS_DIR(DIR)                                \</span></div>
<div class="line"><a name="l00185"></a><span class="lineno">  185</span>&#160;<span class="preprocessor">  do {                                                   \</span></div>
<div class="line"><a name="l00186"></a><span class="lineno">  186</span>&#160;<span class="preprocessor">    if (k == 1) {                                        \</span></div>
<div class="line"><a name="l00187"></a><span class="lineno">  187</span>&#160;<span class="preprocessor">      RUN_PASS(1, 1, DIR);                               \</span></div>
<div class="line"><a name="l00188"></a><span class="lineno">  188</span>&#160;<span class="preprocessor">    } else if (k &lt;= 32) {                                \</span></div>
<div class="line"><a name="l00189"></a><span class="lineno">  189</span>&#160;<span class="preprocessor">      RUN_PASS(32, 2, DIR);                              \</span></div>
<div class="line"><a name="l00190"></a><span class="lineno">  190</span>&#160;<span class="preprocessor">    } else if (k &lt;= 64) {                                \</span></div>
<div class="line"><a name="l00191"></a><span class="lineno">  191</span>&#160;<span class="preprocessor">      RUN_PASS(64, 3, DIR);                              \</span></div>
<div class="line"><a name="l00192"></a><span class="lineno">  192</span>&#160;<span class="preprocessor">    } else if (k &lt;= 128) {                               \</span></div>
<div class="line"><a name="l00193"></a><span class="lineno">  193</span>&#160;<span class="preprocessor">      RUN_PASS(128, 3, DIR);                             \</span></div>
<div class="line"><a name="l00194"></a><span class="lineno">  194</span>&#160;<span class="preprocessor">    } else if (k &lt;= 256) {                               \</span></div>
<div class="line"><a name="l00195"></a><span class="lineno">  195</span>&#160;<span class="preprocessor">      RUN_PASS(256, 4, DIR);                             \</span></div>
<div class="line"><a name="l00196"></a><span class="lineno">  196</span>&#160;<span class="preprocessor">    } else if (k &lt;= 512) {                               \</span></div>
<div class="line"><a name="l00197"></a><span class="lineno">  197</span>&#160;<span class="preprocessor">      RUN_PASS(512, 8, DIR);                             \</span></div>
<div class="line"><a name="l00198"></a><span class="lineno">  198</span>&#160;<span class="preprocessor">    } else if (k &lt;= 1024) {                              \</span></div>
<div class="line"><a name="l00199"></a><span class="lineno">  199</span>&#160;<span class="preprocessor">      RUN_PASS(1024, 8, DIR);                            \</span></div>
<div class="line"><a name="l00200"></a><span class="lineno">  200</span>&#160;<span class="preprocessor">    }                                                    \</span></div>
<div class="line"><a name="l00201"></a><span class="lineno">  201</span>&#160;<span class="preprocessor">  } while (0)</span></div>
<div class="line"><a name="l00202"></a><span class="lineno">  202</span>&#160;<span class="preprocessor"></span></div>
<div class="line"><a name="l00203"></a><span class="lineno">  203</span>&#160;  <span class="keywordflow">if</span> (chooseLargest) {</div>
<div class="line"><a name="l00204"></a><span class="lineno">  204</span>&#160;    RUN_PASS_DIR(<span class="keyword">true</span>);</div>
<div class="line"><a name="l00205"></a><span class="lineno">  205</span>&#160;  } <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00206"></a><span class="lineno">  206</span>&#160;    RUN_PASS_DIR(<span class="keyword">false</span>);</div>
<div class="line"><a name="l00207"></a><span class="lineno">  207</span>&#160;  }</div>
<div class="line"><a name="l00208"></a><span class="lineno">  208</span>&#160;</div>
<div class="line"><a name="l00209"></a><span class="lineno">  209</span>&#160;  <span class="comment">// unimplemented / too many resources</span></div>
<div class="line"><a name="l00210"></a><span class="lineno">  210</span>&#160;  FAISS_ASSERT(<span class="keyword">false</span>);</div>
<div class="line"><a name="l00211"></a><span class="lineno">  211</span>&#160;</div>
<div class="line"><a name="l00212"></a><span class="lineno">  212</span>&#160;<span class="preprocessor">#undef RUN_PASS_DIR</span></div>
<div class="line"><a name="l00213"></a><span class="lineno">  213</span>&#160;<span class="preprocessor"></span><span class="preprocessor">#undef RUN_PASS</span></div>
<div class="line"><a name="l00214"></a><span class="lineno">  214</span>&#160;<span class="preprocessor"></span>}</div>
<div class="line"><a name="l00215"></a><span class="lineno">  215</span>&#160;</div>
<div class="line"><a name="l00216"></a><span class="lineno">  216</span>&#160;} } <span class="comment">// namespace</span></div>
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